So, I used gasket remover to clean off the gasket from the crankcase cover.  Carelessly, I've allowed the finish on the outside to become damaged.

Can I repaint this?  If so, what would be the recommended process, and product, for doing this?

This is how I would do it. Go buy some paint remover, aircraft
paint stripper works awesome, other brands will work as well.

Next buy some primer, I recommend VHT high temp paint. Also buy some wax and grease remover. After you have the paint stripped off, and your ready to prime, take a scotch pad and scuff the entire surface to dull things up and make a surface that primer likes.
Next take your wax and grease remover and wipe the surface really really well to ensure you have a nice clean surface. Follow the directions on the VHT can, primer is straight forward.
Now after the primer is dry you can paint it,  buy some VHT high temp paint, it comes in several colors. Use the paint EXACTLY how the directions tell you to and you will get great results. To cure this paint you can either put your engine parts back on the bike and run it for a while to cure the paint or you can bake the parts in the oven at 200 degrees for an hour. Just be sure all oil and grease is removed from the back side to ensure your not baking that stuff and smelling your place up.
Hope that helps, and like I said, that's just how I would do it. Best of luck, post pics when your done 

Sounds pretty straight forward, thanks.  Is VHT high temp paint easy to find?

Yeah its at all auto parts stores I've been to.

The VHT high temp is good stuff, but just a few additional tips:

1) You should degrease BEFORE you scuff it with the pad. Otherwise, you'll have a tough time getting the grime out of the scratches you create.
2) The VHT requires much higher baking temps to fully cure than what you'll get by running the bike. Use your oven. It's not strong smelling, IF you let it dry completely before baking, like 2-3 days.
3) Once you have the primer baked on, do the same steps again for the top coat, except don't degrease or scuff, unless you contaminated the primer coat. Be aware that your degreaser may remove the primer coat if it isn't baked on fully, or if you use a too-aggressive degreaser.

I've had great success with the VHT header paint, but not on engine case covers, so I can't say how well the finish will match in that application.

Okay, great!  Will brake cleaner work adequately as a degreaser?

Now, what colour do I need?  Is it the metallic sonic silver as listed at http://wiki.gstwins.com/index.php?n=Main.Colors?