Old English Game Bantams questions

I think I have found a place to keep a trio of old english bantys for the summer ,but there is a mixed flock of other poulty there and I am worried about them picking on my bantys, I have a small pen that I could most likely use to house them but I want to make sure it is large enough. It is a 1"x1 1/2" welded wire cage that is 18" wide by 24" long and 18" high. If I put this in a safe draft free place would it be a big enough space for a trio of old english. I just want the birds to supply hatching eggs to beable to sell chicks this summer and then sell the adults off as well in the fall. The old english I see around here are really small 6-8" tall birds so I'm hoping this will work. The cage also is some what like a commercial rabbit cage so it has about a 2" dropping pan in the bottom with a slot to pull it in and out, I thought about putting a 1/4" hardware cloth floor over the top dose anybody have and experience with old english on wire vs. straw or pine bedding?
also will the 2" or so loss in height make it to small? Just hoping I can do this so I can get some use out of hova-bator it's been about 5 years since i was really able to put it to use and not something I want to get rid of.

 

I'm thinking of adding an attachment/ addition for the nest box on the end door to add a little more room. This pen will just be to keep them safe from a standard roo and goose hen that share the house and they would beable to have supervised time out of the cage for about a 1/2 hour a day when i go out to feed and collect my eggs. I will have to keep my breeding stock at a relitives house a couple miles from my own, and want to resell them in the fall so i want to keep them alive and well. I also have an out side veg. can feeder or 2 that i can use and want to find away to make and outside gravity waterer, i have some ideas for making one, i would use a gravity ball waterer like the ones hapmsters use but i don't think the birds would know how to drink from it, so i'm thinking how i can make something that works like a gravity waterer for dogs and cats but mounts to the outside like a gravity ball waterer for rabbits... i think i can swing it with a pop bottle and some hot glue, i hope it works out i really want to get some use out of my bater this summer. The current situation is I have someone who wants to get rid of some barn pigeons and I want to take them to auction to sell as shooters for training bird dogs, and would like to buy a trio of old english with the profit to get hatching eggs from this summer, but first I need to get ahold of a freind who dose the poullairm testing at the auction to see if all chickens at the auction have to be tested or just older bird at a dollar a peice to get them tested it won't be worth it with them only selling in the range of $1-$2.50 and 15% commission