Factory NM match rifle with USGI parts sells for around $1200 if still in great shape/condition.  Question will be if the Fiberglass stock was factory with factory glassing, or an add-on and not glassed in correctly/at all and condition of the glass.

USGI mags are worth $25 each. Type 57's $10, and cheap US clone mags not worth the time of day.

Harris bipods vary in price depending on the model, and same with the drag bag.

As for the SA scope and mount, not worth the trouble since both can be problem children (might be worth something in regards to getting credit if SA will take the scope back in regards to being defective). The mount you should be able to sell off to someone looking for a cheap mount (they don't hold zero).

As for the 99 and the new rifles, you have to look at the parts to see if they are SA inc, or USGI parts.  The receiver and barrel will be SA inc units, so you want to look the rest of the parts (stamp numbers to see if they are USGI or SA inc).