Hi Myrna,
Anyone that has the skill to deploy an alternate solution for you is going to need a lot more information about the framework that your web site is built upon, before they can pitch alternate solutions to PayPal.
For example, a previous company I was with had good success using the Drupal back end, but it had to be customized rather dramatically to fit our site. However, it did allow multiple shipping options, and very intelligent configuration settings. So getting two of something didn't automatically double the shipping cost, for example.
There are some other techie questions in this forum, and I expect a couple of the posters would be useful people to talk to about this subject.
Best of luck with it!

