That is a tough question, but it seems pretty high to me. I would think $250-300 for an unmolested M96, and a little more for a M38. From a collector standpoint, drilling holes in it is a big hit in value.
Does it have a bent bolt? M38 would be bent, a M96 and 96/38 would be straight.
The easiest way to tell a 96 from a 38 is looking at the space between the barrel bands.
On a M38 or a 96/38 it will be about 4 inches. On a M96 it will be considerably longer.
It is easy to spot when looking at them side by side. Here are a couple examples on Gunbroker:
Nice M96 that sold for under $300
Here is a decent M38 with Bayonet that sold for $380
Decent 96/38 that sold for $325.
For What it's worth, my matching Husky M38 the handguard ring is not marked at all.