In store pick-up seen them as low as 65 bucks in Corona California I got a pair of 6 volt reconditioned for 100 bucks here in San Francisco, check out any battery recyclers.
Regular T105s are available from just about every RV dealer in the southwest from what I could see last winter. Every dealer I was in had a skid of them.
All the RV dealers were substantially higher priced on them than this place.
I did have to drive from Quartzite to Phoenix to pick them up but they had pick up locations all over the US, you just named your choice of pick up points when you ordered.
If you're only ordering 2 T105REs it might not make it worthwhile to travel far to get them but for the 4 of them it added up to savings.