hi
we had the same issue, a small amount of ewes so for the first couple of years we bought in a tup and when job was done he went in the freezer but this year we bought a tup (boreray) which we will keep for a couple of seasons until this years lambs are ready for tupping then we'll move him on.
When he's not in with the ewes he shares a field etc with our billy goats, its a good size field so they have space to get away from each other but for the most part they co-habit quite happily. So really it depends if you can be bothered with looking after him for the other 11 months of the year but they are easy to keep but it would be worth keeping a wether for company for him so he wont get lonely.