The Astrolux FT03 from Banggood is the best budget thrower of the year AFAIK. It can use an 18650 with the included adapter.
If you’re interested in it, you’ve come at a good time to buy one. Freeme is hosting a groupbuy for new colored versions of it (green and blue) for around $28 to $33.
The groupbuy is here: ✌ FREEME - ASTROLUX FT03 in BLUE & GREEN - Arrived! Just comment asking for the code and he’ll PM you. Ordered mine yesterday!