Trying to find a decent source of cheap-ish OEM wheels with the above sizes - any ideas? Seems to be endless Audis and Mercs use the bolt arrangement but the staggered width and 10j seems to be fairly hard to find.

ebay.com, 8j easy and cheap, 10j more difficult, if u can get an adaptor to change to 5x114.3 you have 1000's that size to choose from, you can get sets on ebay.com for under $500, the find a local car shipper to ship then in one of his next containers for a few £

here is an adaptor 5x4.75 (120.7) & 5x112 to 5x4.5 (114.3) Wheel Adapters | eBay

just had a quick look on ebay.com and it seems u can get 17x10 in the 114.3 but only a few, but a much bigger choice if you go to 18x10 and 18x8, nothing in the 5x112 that size.

i have 18x10 and 18x8 on my kit and they look good, i have an unfinnished viento

I didn't want to go up to 18's for cost reasons - I suspect I'll be shredding 285's fairlyfrequently and in 17" they're still fairly "cheap" and have enough sidewall depth to deal with road use. Plus may have enough compliance to give me some indication before they snap-spin me into a hedge

I'll check out the converter idea, cheers - might make life easier I suppose - I'd been looking for "native" wheels as im not too keen on extra mass and failure points for no reason but since I seem to be really quite limited by the audi hubs I'll have to work with what I can.

the 18" wheels are so cheap, £200-£300 a set of 4, and 18" tyres are normally cheaper than 17's because they sell more 18's, check out camskill for prices of tyres before u say no to 18's