Custom/rare step up ring sizes

[earthmanbuck]

I just bought a LTM Canon 35mm/2.8 on eBay, and I would like a step up ring for it that goes to 49mm—just because it's the least obtrusive size for which I already have lens caps and filters. I have a couple questions:

1) The seller says the lens has a filter size of 36mm, but most of what I've read suggests it might actually be 34mm. Is anyone here who knows these lenses able to say for sure? It's the all-chrome version, and it actually says Canon on it, not Serenar.

2) Is there somewhere online that sells step-up rings in less common sizes, or can custom make them without being too pricey? I did find a few sites, but nothing that had 36mm in anything other than 36-37, and while I do have a 37-49, I would like to use as few rings as possible. (I had a similar problem when I bought a LTM Canon 50/1.4 a while ago, but was able to eventually find a 48-49 ring).

Thanks in advance!