Broken Rear Engine Mount Bolt - Replacement Specs?

[JohnOfTheJungle]

So, last night it was about 27 degrees out. As I turned to get onto the Williamsburg bridge, accelerating from a stop, I failed to see the patch of ice that formed from the leaky fire hydrant 10 feet up the hill. The ass end came around on me, causing me to drop the bike on its right side.

Luckily I was only going about 3 mph, so I didn't even fall, and I picked the bike up quickly. The bike is already beat up and had been dropped many times by previous owners, so I wasn't worried about cosmetic damage. Gave it a quick once over, then rode home.

Tonight while out on the bike I noticed something peculiar - a sheared engine mount bolt sticking about an inch out of the engine on the left side (which is not the side I dropped the bike on). So I rode home gingerly, keeping an eye on it.

I'm gonna have to replace this thing -- does anyone know the specs offhand? Otherwise I could shell out $25 for an eBay replacement, but would be great to pick one up from Home Depot for $3