With the season closing in (like less than 2 weeks) you better pull the trigger quick, get the gun, a few different projectiles, some pellets or loose powder and start practicing if you plan on shooting 175 yards.
You are going to have to find a projectile and powder charge that will give you accuracy. Working up that combo for a black powder rifle is similar to a reloader piddling around with CF rounds.
Not trying to discourage you, but you are way behind the eight ball here. These take a bit of getting used to and load/projectile work-up is key.
For just under 400 bucks you can get a "everything you need kit, less the powder, including a scoped rifle" from Traditions (Scoped Deer Stalker model). Unless you think you will actually keep up using this year after year this may be your best bet.
Otherwise you could easily lighten your wallet by 1500 bucks if you go with a Knight rifle, add some glass, then buy all your "needed" accessories to go along with it.
And since you are asking the question you did, it sounds like you are totally new to black powder.
Regardless of what you get it must be "meticulously cleaned" after every outing or it you will have a rusted mess in very short order.
With the rut being unpredictable and not occurring in some places in Ontario this year we have seen a rush in sales on Black Powder guns and Crossbows. I expect to see many of these listed on the "used gear listings" in a year or two when guys find out these DO take considerably more practice and work than they first appear.
