IMO, lots-of-luck finding a really good looking ADULT female. Unless you come across one somebody has as a pet that no longer wants her. I know all my really good looking females aren't going anywhere. I am planning on replacing some of my "lesser" females with brighter stock over the next few years but again, not my best ones.
Again, IMO, don't wait, start looking for a hatchling or two now. and if you want a really nice looking one, don't scrimp and buy the cheapest, look at pics of the parents along with the baby and if you can, wait for the holdbacks to come out. I have not sold any of my best yet, still deciding which ones to keep and I'm sure other breeders are doing the same.
Some of my not-for-sale holdbacks:



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Thanks,
Dave "Rainbows-R-Us"
0.1 Wife
0.2 kids
4.12.136 Brazilian Rainbow Boa (OK, I'm only keeping a few of the 136, just tickled pink with my production this year)
1.1 Ball python
0.1 BCI "Elvira" normal from 1989
1.0 BCI albino / het-anery
0.1 BCI Hypo / het-albino
0.1 BCI Anery / het-albino
0.1 BCI Hypo (possible super)
1.0 BCI albino het stripe
1.0 BCI salmon hypo
0.1 BCI ghost
lots.lots.lots feeder mice and rats 