BJPA adverts show the 16.5cm Heliar being sold separately in 1927 in different mounts and also in a Compur/Compound, and by 1929 on the 10x15 Tourist. I wouldn't sell it with a modern camera, you'll most likely get less, I'd find a Xenar or similar to go with the camera and remove the Heliar & flange. I'll have a few adverts etc maybe other information if you want any scans. I'll look later what info I have prior to 1727/

I quite like 165mm I've two Tessar's an f6.3 & a rare f5.3 in that focal lenght and I use them on two half plate cameras, they are excellent on 5x4 and so would your Heliar, plenty of room for movements.

Remember there's a serial no on the Compur which along with the lens sn should give you a reasonable idea what year it was made.

Ian