Janine,The APA accepted weights for silkies are: 36 oz cocks, 32 oz hens and cockerels, 28 oz for pullets. So, your pullet is 28 oz. (or 28.8 oz depending on whether you're going by the pounds you stated or the ounces). Either way, she is not too heavy at all.
I should have asked how old she is: if she's 4 months old then she's larger for her age. If she's 8 months old then she's perfect! LOL
Did you ever hear back from ASBC about split wing? Weren't you checking on something else as well?