I'll defer to others on the calibre ?
As for scopes I 'll add to the saying" you get what you pay for", " you pay for what you can't see"
Probably the best scope in the world is made by SCHMIDT & BENDER and the most exspensive. There probably ugly enough to make an onion cry.

buy a rifle from a maker that its tried and true, flip a coin on caliber, buy the best scope money can buy because a cheap one will fail you at the most critical time you'll need it (If you don't be live me do it he cheap way and you can find out for yourself). Good luck and buckle up.