Thanks for the info GrayJay.
The bike will only be used for easy riding by me, but the fella I bought it from used to race it amongst the elite in Norway back in the 90's so the crank has probably had it's fair share of wear and tear.
I will deffo inspect the cranks from time to time.

I probably also will replace the crank cause I've actually been on the lookout for a 39t small chainring, and wasn't aware SR had 144 BCD.