Jai,
I know a lot of people get their seeds from Silverhill seeds in South Africa, but they just lost their two main owners due to a horrific incident linked to terrorism (you can find a thread on it at Agaveville and it made the news in the UK for sure - they were UK nationals if I remember correctly). However, I think the store is still in business and people over on Agaveville have been very positive about the seeds received, before and after the incident.
I think there is a place in Oakland the institute for Aloe studies, but they do not sell seeds, they do sell plants though:
http://www.aloestudies.org/sto...
You have to wonder why they do not sell seeds... anyway, maybe this is at least somewhat helpful.
