If you cross your RIR rooster with your Silver Laced Wyandotte, your will get Red Sex Links which can be sexed by color from hatching. Male chicks will be whitish and female chicks will be reddish. You can also get Red Sex Links by crossing your RIR rooster with your White Rock hen if your White Rock hen has the silver gene factor (some do and some don't). I've raised Red Sex Links for years and they are egg laying machines, outlaying either parent breed. It's one of the interesting quirks of hybridization. You can see the differences between the RSL chicks and adults in the two photos below.
Whitish male Red Sex Link chick on the left; reddish female RSL chick on the right.
Googled from http://www.freyshatchery.com/images/red sex-link.jpg
I just hatched out some Rhode Island red rooster crosses. So I'm not to sure what they will look like in the further, but the feathers are coming in nice.
I can get pics directly of the wings and out of the light as well.
I also hatched out a RSL possibly to a RIR rooster. She is very pretty, I'll need to get a pic.
Gold (Red Sex Links) can be produced by crossing any red gene rooster (RIR, NHR, Production Red) with any silver gene hen (RIW, SLW, WPR, Delaware, Lt. Sussex, etc.).
These are my two they are about 2 months old. I think the smaller one is a hen and the bigger is a boy. But there as been some debate on the smaller one. What do you think?
