Traditionally, people write linux drivers for things because they have a specific need. You might be able to find someone who would do it for money, but you might not. The fact that there has been no progress on PCMCIA sound support reflects two things: implementing it is hard, and few people need it. Only a tiny minority of linux PCMCIA users (who are themselves a tiny minority of linux users) have any use for PCMCIA sound cards, because the vast majority of commercial laptops come with sound support superior to what could be done in a PCMCIA device.
I know someone at DEC did some work to develop a custom kernel for an ARM-based system to support a PCMCIA sound card. It was a very specific hack for a very specific hardware platform, and the trick is not applicable to other architectures.