RM125 (1993)

Hey everyone. My son got a project bike- RM125 1993 and it was missing the power valves and valve guides. He’s managed to get everything he needs except the right hand valve guide. Apparently the parts have been discontinued so it’s been a nightmare to get the parts.
We’ve come across a few sites that suggest the guides may be interchangeable but I’m not sure if that’s accurate. Has anyone rebuilt one and can tell us if they can be or not? The exact part number we need is: 11261-43D00 (it’s a type P).
Thanks for any help you guys may have.

I didn’t think of a motorcycle salvage yard, that’s a great idea! I’m going to see if there is one semi local. I did try calling a bunch of places who tried to help me locate one but when they didn’t turn up any options, they didn’t have any other suggestions in terms of a part that may work in place of the one I need.
Thank you for your help!