Yoletrapper,
Yes, Lavender can be in any breed. I have had Lavender Silkies, Lavender Ameraucana bantams, and right now I have Lavender Ameraucana Large fowl, Lavender Araucana american type and working on them to make them tufted rumpless, and I have Lavender Araucana UK type look-a-likes. Sold my Sumatras or I'd have Lavender Sumatras in good time. First you need the gene and that is easy if you are working on a bantam breed but there are very few Large fowl with the Lavender genes so you'd have to build one up from bantam stock first. It should only take about 5 to 10 years till you get there. I had a Lavender OE large fowl hen but she had extra genes that I did not want to clean up so she had to be sold.
I just seen some albinos in an Australian site and a black albino appears to have the soft grey color similar to a Lavender. Maybe you can find an albino chicken that lives long enough to breed. I really think it was some type of Pheo dilute myself because it didn't have red eyes but I don't have the chicken to breed it to know it's exact genetic background. It also appeared to be a sexlink gene but that would have to be proven after breeding it several years. Good luck in you quest, Harry
PS just hatched 13 Lavender Ameraucanas this weekend.