i like the look of the horsehair sporran...i was thinking about getting a synthetic one and shorting the hair so that it looks smaller - not so overwhelming.
Most non-military Victorian sporrans you see in pictures are goat, not horsehair (If I can ever find a decent cantle, I'm going to make one. Fashionable or not, I really like the look with evening wear).

1. They're supposed to be overwhelming. Consider the Argyll officer's full-dress "swinging six":


2. The synthetic horsehair sporrans I've seen are shiny slinky snow-white Barbie-doll hair or something; not at all what I'm looking for in a sporran.

3. If you cut it, it's yours forever; it'll have absolute zero resale value. Everyone will look at it and think it's a butchered horsehair sporran, and wonder why on Earth somebody would do that.

Unless your company function is extremely formal I would not suggest wearing a PC to it. The PC jacket is pretty much the formal equivalent of a coat and tails. The PC is great for an formal embassy dinner or a groom at a wedding, but not your run of the mill formal event. If the other guys will be wearing regular tuxedos then I would suggest wearing a black Argyle jacket instead and consider wearing a semi-dress sporran if you don't like the fur sporrans.
I'm quite positive that I disagree with this statement. Think of a Prince Charlie (with waistcoat, tux shirt & black bow tie) as the equivalent of a tuxedo; an Argyll jacket (with oxford shirt and Windsor-knot tie; with or without waistcoat) as the equivalent of a business suit, and a tweed jacket as the equivalent of a sportcoat.

While I go black tie all the time, I've only done two white tie events in the past five years. I simply change out my black waistcoat, tie, & studs for white. I wear Argyll hose, buckle shoes, plaid & dirk to both.