Yes, that is a 1996 frame, and it looks in excellent condition from what I can see. I would expect the weight to be about 1.95kg, so if it has an LX bb and not forgetting the headset cups weigh c70g, that corresponds to your as-pictured weight of 2.3kg.
I don't see the dog collar canti guide, so does it have a braze-on V-cable stop? Only the later 96 Kilaueas have a braze-on stop, so if yours has one it would be well worth saying so. Also I assume you're selling it with the Kona clamp, but it isn't pictured, so if it's included in the sale it would be well worth saying so.
The triple-butted P2 should raise £25-30. If the Impact is in good shape, it would be best to remove it and sell it separately, as it's worth £10-15 and might help the P2 to sell well if sold at the same time. If you still have the Velocity stem, that's worth £10-15 also. And the O-Beam £15-20. And the dog collar £10-15. But all subject to the caveat that eBay is very unpredictable! And you might well find it possible to sell them on here.
