Mesh modern to my 5 speed

My Condor runs 5 speed. Thing is I've not got the gears just a 1977 Super Record chainset.
I can't find a 112mm asymmetric bottom bracket either.
So I was thinking of running a new chainset with a modern'ish friction set up with the old 5 speed free wheel
Anyone done this, or know of any pitfalls

Are you saying you can't find a bottom bracket spindle to take your S.Record chainset ? I find this hard to believe.

Yep 112mm asymmetric, all new ones are symmetric. None are available new anywhere.

I'm tempted to buy a new track chainset and fit a singlespeed freewheel to the hub. Will that work. The hubs 120mm.

Couldn't you just use a longer BB spindle and accept a couple of mm of offset?

Yeah, I'd consider the total resultant offset. Bet it isn't much. 8-speed Campag will probably see more cross-over at the extremes than your offset setup.

Having had a google people seem to use a combination of Stronglight spindle and spacer behind the block to negate the offset impact on the chain line.

You could use a Miche Primato BB as they can be installed at an offset,

^ This or phil wood.

TBH I don't think it'll make much difference.

I'd be interested to know what this offset is likely to be around, in milimeters.