MM Cartridge recommendation

Can't go wrong with this Audio Technica VM750xSH

The DD-5 is a design launched into the Market 50 Years ago, from the era when TT's were going in new directions, the Belt Drive was to dominate shortly after the era.

Think of it as a very very early Tech' that migrated to Tech Das.

It is also believed by some to be a version of the Tannoy-Micro produced in thr same era.

There is plenty of enjoyment to be had, and learning to be attained.

I recommend to be inquisitive and to be willing investigate variations on methods for mounting/supporting the TT, a discovery made through making changes can be very very satisfying and wanted to be kept in use.

Also a 50 Year Old Platter Spindle Bearing - Unknown History - Benefits can be found from learning what to do for the servicing of this part. 

Congratulations on scoring a very nice turntable.  I understand that it is fitted with a MA-303 tone arm which has a medium effective mass.  So any medium compliance cartridges should suit but avoid high compliance cartridges or low compliance ones.  I agree that it would be sensible to check out moving iron cartridges; there are some beauties amongst them.  Enjoy

+1 for VM750SH (I can’t speak to ‘x’ line). Detailed and warm. But not sure on your tonearm effective mass. This cart doesn’t need much weight at all.