Most baldricks need to be sewn by someone with access to the intended wearer or they end up not fitting too well, but if you can tack the bits together (just a few soft stitches to hold the various pieces how you want the finished job done, use a contrasting colour thread so that your rough work can be easily unpicked later) Manitas' suggestion of the local dry-cleaners may well find you someone local who can finish-sew them quite easily. Perusing the small adds in the local paper or newsagents window could also lead you to somebody who can help.

If you need leather stitching a handbag/shoe repairer may be able to help, or an old-fashioned cobbler or saddler, though I would expect the latter to want "county custom" money. Any of these will need you to show them what you want, as few will have any idea what you are aiming for.

If your bells are mounted to a pad, or to a leather strap, you can save a lot of sewing by punching a small hole where the bell goes (a bit under 1/4" should do) then just push the bell loop through and keep it in place with soft wire or string. This also allows for easy replacement of a bell that has got crushed or lost its ringer. I used small split rings for a while, but they snagged on my socks when wearing breeches. They would be OK if your side wears trousers.

I assume your side will bulk buy the bells and issue the appropriate number. If they have no side-specific rules on layout I would counsel keeping the largest bells at the top, and not directly in front of your shins, this will save on bruising.

Before buying in bulk was the norm one dancer of my acquaintance went into a pet shop and asked for 3 dozen budgie bells in G (he was a melodeon player) Once the assistant had grasped that he was entirely serious, our hero spent a happy 30 minutes or so selecting his bells by ringing them one by one in his ear. You can get quite a name for eccentricity, even before you dance a step in public, if you go about it the right way.