Weird pulley, need help!

Hello,
This is the pulley that i found on my Murray:


Does anyone know what kind of pulley this is? Why is it on there instead of the normal design that has the V- shape where the belt sits. Can i modify the pulley so i can run a belt without slip?
(I put the belt on there, pulled on it by hand and then tryed to turn the pulley, the pulley turned with a bit of friction.... The clutch spring wont be enough to keep the belt from slipping when it get wet or when i hit a hill) I have a welder and angle grinder, if you have suggestions please tell me them!

Transaxle? Yeah shouldn't be that big an issue to change it to a V pulley.

@MightyRaze Its a peerless 700 gearbox. Imma weld something onto the pulley to get a v shape and then it should work!

That was on a Murray?! Looks like a MTD VariDrive pulley so that 700 could be from a VariDrive with Hi/Low and only be a 2 speed? What are the numbers on the case?

@Brianator
Yes, it is on a murrray. My offroad lawntractor looks like a murray 11/36, there sadly is nothing on the hood, so i dont know for sure, sticker got removed.... I can only say that the chassis seems weak, i want to build a wheel horse type one in the future for it. Now im just throwing it back together and send it till something breaks....
Weird thing is: It came with a peerless 700 transmission that has 5 forward gears (its pretty rare i think), it looks like it came from factory with that transmission, cant find anything on google about a 11/36 with the peerless 700. Where can i find the plate with the numbers on the transmission case, searched it and did not find it....

I'm not sure where on that, if it only had a sticker it's probably gone but there are usually casting numbers embossed on cases and sometimes you'll find a model and serial number etched in on a flat machined area. That pulley screams MTD VariDrive to me BUT... some of the older Murray built Sears/Craftsmans did actaully have that setup with a Peerless 700 transmission right under the seat powering a transaxle. Can you upload some pics of the tractor?

@Brianator
Let me tag you under a post that i made a while back about my murray, there are some pictures. The transmission indeet sits under the seat.

Ah yes I remember now, thank you for refreshing my memory! Wish I could help about the pulley but I'm a confused as you are about it, I'd personally ditch it in favor of a standard v belt pulley for better belt "gription"

I’ve seen pulleys with a squareish groove on Murray’s, I think it was just a cheaper way to stamp out a pulley for a low torque application. My peerless 700 I use for a winch gearbox has a standard 5/8” shaft with a 3/16” wide key. You should be able to order a regular V belt pulley to go right on.

@RichieRichOverdrive
Thanks for the informations!
Imma check if i can find a fitting pulley online, idk if there are some aviable here in germany.
Here in germany, we also dont have the Weld on pulley parts you can get at tractor supply in america.... have to make such pars at home

@Brianator
Today i took some gasoline and a old rag to get the spraypaint off of the hood and found a sticker that says: Murray 11/30. So my mower is a murray 11/30.... Weird thing is: i looked online and saw nothing about the murray 11/30 coming with a Peerless 700 many of them say ''Transaxle'' over the shift lever, i dont get it

If you have access to a little lathe it’s easy to cut the center out of your old pulley and weld or bolt it into a new pulley. I do that sort of stuff all the time. You can also try your luck and just hope you can cut the old hub off with an angle grinder and weld another one on centered enough

Right on but that 0 has to be a 6 so it's a 11/36, 30" is Rear Engine Rider territory and you clearly have a ride on tractor.

@Brianator
Yes, it is a Ride on tractor. But it still says 11/30 on the fenders.....

@RichieRichOverdrive
Im maybe gonna do this. I found a german website that sells custom pulleys, sadly they are made out of cast iron, i dont know if its so good to use it on a mower thats constantly having load changes when driving or pulling something.

Cast iron is fine.  It's when you get into the aluminum that things break down and fall apart from use.

Cast iron is a good choice! The only drawback to a cast pulley is they have a lot of inertia, which makes shifting on the fly a bit hard with a shift key type transaxle.