Hi, how many pins is "several"? And how far apart are they? Are they all neighbors?
There are various sources that repair missing-pin CPU's, but they usually charge a bit ($20-$40 plus shipping). You can also sometimes find local jewelers who might take on the challenge and solder a new pin on for you.
Otherwise, if the pins are not next to each-other, sometimes placing a pin in the appropriate socket hole, then installing the cpu on top of the protruding pin can do the job if there are relatively few missing pins and they are not adjacent to each-other. If they are adjacent, it could be difficult to prevent them from attaching or shorting.
The backyard version of cpu repair above involves trimming conductive pins to the appropriate length (you can usually get a pair of needle-nose pliers and extract pins from used/salvage ethernet card connectors or other cable/connectors) then push them into the socket in the CORRECT placement. If they are trimmed to the correct length, installing the CPU and mashing the cpu atop of them can often times make the needed connection and work. I wouldn't move the PC around while using it if your pin length measurements aren't very good.