I think that even if you can find a company that will insure reptiles for life or health, it would be very expensive. And the huge variety of reptiles with such a wide variety of care needs makes underwriting the policies almost impossible.
Not to mention the potential for fraud...
What you should do, though, if you're worried about losing an expensive animal, is self-insure. This means that you are putting money away each month as if it were being used as insurance premiums. This money would only be touched in the event of the loss of a pet, veterninary bills, or whatever. You could decide how much you could afford, and you'd know you always have the money there for when you need it!
Just don't go out and buy that new morph with the money, and then you'd be back where you started! 
Anyways, that's my 2 cents, from someone working in the insurance industry. Hope it helps.
Nicki
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1.1.0 Uromastyx maliensis (Mali Uromastyx) - Spike and Lizzy
0.0.1 Lampropeltis mexicana thayeri (Variable (Thayer’s) Kingsnake) - Kavi
0.0.1 Lampropeltis triangulum campbelli (Pueblan Milksnake) - Callia
0.2.0 Thamnophis sirtalis parietalis (Red-Sided Garter Snakes) - Spot and Fluffy