So, long story short, when I bought my RRS it only came with one key. Original owner had "lost" the spare. Anyway, I've tried main dealers for a replacement, only to be told they are "on long term backorder" with no sign of an ETA.

My question is, will any new fob such as the ones listed on eBay as genuine work or is that just a scam?

I've got the IID tool so that side of things should be fine, just don't want to waste over £100 on a supposedly genuine unused key if it won't work. 2014 L494 HSE