E-Commerce

I have what appears to be a more unique store that doesn’t fit the available plug-ins for WP E-Commerce. I’m wondering if I should change to a different commerce plug-in.

https://www.berrytanglefarm.com

I want customers to be able to purchase a minimum/maximum amount of variant categories (e.g. at least 2 Orpington eggs but not more than 5; at least 3 Icelandic eggs but not more than 7, etc.) and have shipping figured by a batch amount but not combined (1-12 eggs per flat rate shipping and 13-24 is another flat rate shipping; eggs and chicks are shipped separately so either the customer can’t purchase both in one transaction or the shipping must be separately figured). I also want to be able to show variant categories as out of stock (can’t get that particular WP E-Commerce feature to work for some reason) when the Orpington hens are broody and not laying, etc., and show how far out the order could be (mark Icelandic chick fulfillment as 3 months out and Orpington chicks as 1 month out, etc.).

If that makes any sense, please let me know how to do some of that and if I should change e-commerce plug-ins to get it done.

PS. I’ve tried to get the min/max purchase plug-in developer to help me since the plug-in isn’t working, but haven’t had any luck.