Here, take a look at the lock portion at least,
http://doubleshotguns.com/ugarUC5.htm
The wood on the ones I saw was tempting. This is something that you need to figure out on your own. I don't like ejectors so that put me in the graade I or II area anyway; but that wood was
very tempting. With a little work my grade I is starting to look nice, a little steel wool and boiled linseed goes a long way. So if you need a gun that shoots sweet, get any model; need a gun that looks sweet, get a IV. I'm getting attached to mine spending 45 minutes an evening hand rubbing it. Once a day for a week, once a week for a month, once a month for a year, once a year for life. It is drawing out the bit of tiger-striping it has.