06 or 07 would be about right.
You have a Model 1905 (to most of us).
Pearl is not really rare in that period. It was quite popular. Those grips are probably aftermarket, not factory. Most factory pearl and ivory had medallions in that period, even though the wood grips did not usually have them.
It might not be a bad idea to trade for a more modern gun, but you probably won't be able to get an even trade because it is not super rare and condition is everything for the standard M&P's.
Curious- how can you trade a gun that is "loaned"?