My statement was wrong - you are all right - the 10's & one 8 are well under $5,000CDN.
: 4,500 pounds is indeed, almost $9,000 cdn - but- I'm not interested in 8 bores. 8 bores are not allowed here for migratory game birds. 10 bore is the limit. I could see shrotening the tubes (ouch) to 26" and installing sights - maybe oval-grooving one of the tubes in a nice slow twist, maybe 1 turn in 100" for round ball, yet it would still shoot fine with shot for rising birds.