They only make 1 Height for a "See Thru" Ring. It's X-High. I have a set on my Custom 10/22 to give clearance to a 6-18x50mm Scope that also has Adjustable Objective.
WalMart has some for around $20 I believe. Don't know of anybody using these type Rings on an AR Rifle because of the heigth of the Front/Rear Sights and how the See Thru Hole is formed in the Rings. Just don't think they'll work, but I don't know what type/style sights you have---there's many variations out there.
I think this is why when you mount a Scope/Ring Package on the AR many Folks opt for the QD type mounts to use their Irons.
The problem you will run into will be that the scope will be so high above bore that you will have a hard time with cheek weld for the scope and may lose some adjustment in elevation if you get it to high above bore. Youse be better off with a set of quick detatch rings or a detachable mount.
If you have to go the see through route and can't find one the right height, you could check into some risers that the rings could mount to. UTG makes some cheap and effective risers(about the only UTG stuff I recommend on any regular basis).
I have a Marlin .30-30 that had see through mounts. Just never could get comfortable with the scope in those mounts.
Sorry about that. Things sure changed within last 15yrs since I got my Rings. SSGN has a good idea with a Riser which I hadn't thought of. Will take some good measurements, but does look doable after seeing the Ring possibilities. This has become interesting. What kinda Scope you thinking? Del