Many of us use LiPos that don't require anything other than plugging in and inserting into battery compartment. Not sure if A-Main has them but the Intellect 2300mAh 2S LiPo can be purchased from ebay for $20 with free shipping worldwide. Actually, I think maybe I've seen an uber-expensive LRP 3600mAh LiPo that will also do the job, albeit for WAY more than $31, which is 57% on top of the price of the Intellect (that's how much more capacity the LRP has, so logic would suggest the price should be around the same % higher). Might be around $60+ I think.

Dunno about locking out the trims (not even sure how you would go about locking or unlocking them if you could), but you could always just disable them/remove any function from those positions.