The Revelation 310 is a Mossberg 500.
The 500 is a good, tough shotgun and will do fine as a home defense gun.
You can buy a short wood police type forearm from Brownell's. Part number 29, a 6 3/4" checkered wood fore arm:
http://www.brownells.com/.aspx/pid=0...500A__12_Gauge
You can also buy one from Gun Parts Corp:
http://www.e-gunparts.com/products_new.asp?CatID=8024