a 1V will set you back about $2-400, a 3 or 1n are about $1-300, a 5 might cost you $50-100.
Besides those few, almost every other EOS film body are less than $30. Try out a rebel or something for extreme compactness. If you don't like whichever body you get you can just onsell it for a net loss of shipping-cost (if that).
I use my 40mm on my EOS 3, it works great for street-shooting with the eye-control focus, and it's not too big for me (although it's a lot bigger than my Bessa R3A with Nokton 40/1.4).
Regarding AF, be aware that there was a product advisory about the AF on the 40mm not working in certain circumstances.
It only affected the first few made (like mine, I bought it the day after it was announced), it happens on my 3 (and d***l) occasionally, but the disconnect-reconnect workaround works (I've never updated the firmware for a permanent fix, because I don't have a 5D3 or 1DX to do it).
If you've bought it recently, no need to worry about any AF issues.