Yes of course, the Ducati singles had that bevel-driven OHC. And are very desirable. The bigger ones are highly valued collection pieces by now, don't know about the 160. Looks like the engine from this:
https://motorcyclespecs.co.za/model/duc ... a%20jr.htmIt's obviously a Café Racer. Bikes like that are not uncommon in the UK, or elsewhere in Europe, and that on it's own shouldn't be a problem for registration.
But if you don't have any registration documents (either UK or foreign) matching that frame, I think you'll be looking at quite a stiff technical examination. Not sure exactly how registration without previous other registration documents (or a Certificate of Conformity) works in the UK, but I have done that in NL. At the time ('95) there were two possibilities: a) if the bike conformed to a Type Approval (so a model previously approved for road use), but does not have a CoC to demonstrate that, there was a relatively simple & cheap technical tests to assess compliance with that Type Approval; and b) if the bike did not conform to a Type Approval, the test were far more stringent, and particularly: more expensive. It will then have to conform to all current requirements, which I fear will also in the UK currently mean Euro 4 (until Boris changes that, of course). I fear your bike would fall in category b).
If you do have a (foreign) registration document, registering it with the DVLA is easy. That I have done, and nobody needs to see the bike (other than for an MoT).
But maybe it's all different in the UK nowadays. Best check with the DVLA.
Good luck!