I would recommend emailing us at Techsales@opticsplanet.com and letting us know what features, budget, and mounting options you were looking to get with a scope. This way we can more accurately recommend a scope and ring/base setup that will fit your budget and provide the functionality you're looking for.
I recommend using the Talley Lightweight Alloy Scope Mounts at the link below to mount the Burris Fullfield 3-9x40 E1 Ballistic Plex Muzzleloader Scope to that muzzleloader.
https://www.opticsplanet.com/talley-lightweight-alloy-scope-mounts-for-knight-thompson-center-tikka.html?_iv_parent-gun-make=cva&_iv_parent-gun-model=cva-optima&_iv_code=9E-MT-SMKTCTK-950752&_iv_gun-make=cva&_iv_gun-model=cva-apex,cva-optima
To mount the Burris Scope Fullfield 3-9x40 E1 Ballistic Plex Muzzleloader Scope on that muzzle loader I recommend using the Burris Xtreme Tactical Picatinny Style Rail 1 inch Weapon Rings at the link below. I suggest using the medium height set of rings which are model number 420181.
https://www.opticsplanet.com/burris-xtreme-tactical-1-two-rings.html?_iv_code=BR-RR-XTR1In-420181