Very nice. The green stock guns are the least common, and usually the most desirable.
This rifle was available as the Parka Hunter in 20" length, and the Parka Para in 16" length.
I have not seen a full length version come up for sale. However, the last green Parka Para on GB so for $660. The one before that, sold for $550.
Value on these is hard to gauge. They are not as well known, as many other Commercial variants. Most people just assume it's a Bubba job and keep searching. Only the hard core Chinese collectors know this model.
It could sell for $350, or it could sell for $850. It's just going to depend on how many people seeing it want it at the same time.
Personally, I'd say anywhere from $550 to $650 is a FAIR price. Any more is a bonus. I would not take less than $550 for it (I currently have the para version). If you list it on GB, just set the reserve for whatever number you're comfortable letting it go for.
I also back up Martin's feelings on his... my Parka Para is one of the best shooters I've ever had.