Have a look at my excel file in my Dropbox. (Link in string sticky.)
The tension of very different strings is recalculated to the same vibrating string length, so you can at least find strings that have a tension that fits to the others.
Silk ends can be cut as long as the is still an inch or two of silk is left and secured with a drop of glue. But hard to sell cut strings.
Often people let the ends stick out of the pegbox/headstock and just wind a bit of silk onto the peg. Not nice to see but better to sell.
Or get NS EUB strings (the traditional are shorter D’Addario Orchestrals, I think, the contemporary are longer low tension bass guitar strings). And they are available from low B to high C. But they might be a bit too short …