AFAIK B&O never made a moving-coil, and even if they did it wasn't fitted to this delightfully-designed parallel-tracking TT.
A MM stage/pre=amp will do the trick therefore. NAD, Cambridge Audio, Pro Ject and Rega all make models under £100 which will be more than good enough. None of these is currently listed in WHF magazine, a few having been, er, tidied up a couple of months ago. The Cambridge is still on the website here: http://www.whathifi.com/review/cambridge-audio-azur-640p
but I think it has been £99 for a while now. All of these have been discussed on the forum, so may repay a few searches.
I would just caution that you check it is working OK and has an intact stylus before proceeding. There is an interesting website with all things B&O called beocentral.com which does the products justice and seems to be the work of enthusiasts.