It is an original "Made in Germany" item hkg3
Is it a G3 or a HK 91? A "real" G3 is a select fire weapon, the 91's were/are the semi auto version of them made by HK.
I had two HK 91's, bought them new back in the 80's for around $5-600 each.
Both had bipods, but they were mounted to the tropical handguard, and they were mounted forward near the front of the handguard, and folded rearward. They were not adjustable and actually, pretty annoying to shoot with, especially when folded. They were to high to shoot with except in rare instances where the ground in front of you fell away. I usually took them off the guns.
I also had a port buffer on each, and its an item you want if you plan on reloading. I stops those nasty dents in the cases.
I had carry handles too, but like the bipods, they got little use.
I had both commercial HK claw mounts and ARMS claw mounts. The HK mounts are expensive and have the rings attached. They are limiting in use, and unless you like the German way of mounting a scope, that is, to far rearward and to high, they pretty much suck. The ARMS mount is much more versatile and just as reliable as the HK mounts. They are also about half the price.
I sold both my rifles about ten years ago now. Both sold for right around $2000 each then, and that was for the guns with the carry handles, port buffers and one mag. I sold the HK claw mounts for close to $400 each.
$2200 today seems like a decent price, if it is an HK. I've seen a few selling for $3000+ with no real accessories.