Conversion of the licence and instrument rating will not automatically transfer any other privileges. A type rating may be transferred from a non-JAA licence to a UK issued licence subject to:
- 500 hours experience as PIC on type*
- Operational experience on type within the preceding 5 years
- Passing the approved type rating theoretical knowledge examination
- Passing the relevant Licensing Skill Test
*Since the UK do not issue SIC type ratings only flight time as PIC counts for type rating transfer.
As you are talking about the conversion of a CPL/IR, I assume that the B737 rating in question is limited to SIC. In this case it cannot be transferred to a UK issued licence but the rules in Romania may be different.