There are a couple of cheap fixes for you dilema. There are some stick on/adhesive type combs made by a company called D&E. They are popular with shotguns that need their comb raised. You can find them at gunshops/trap&skeet ranges.

I found this one at Cabela's, it's a made of soft leather and is tied on with a leather lace. It looks a little goofy but does stay in place, even on this 416 Rigby.

One thing to remember it that whatever you use make sure that the comb you attach doesnt interfere with the bolt.