Innolasers offers small laser diode drivers: https://innolasers.com/shop/index.php
High Efficiency Miniature Laser Diode Driver:

Micro Flexdrive V5
$19.99
Micro Boostdrive is the perfect driver for portable:

Micro BoostDrive
$19.99
Low cost linear regulator driver:

Groove V2
$10.99
Analog modulatable laser diode driver:

FlexMod P3
$35.99
High Efficiency Miniature Laser Diode Driver:

Micro Flexdrive V5
$19.99
Micro Boostdrive is the perfect driver for portable:

Micro BoostDrive
$19.99
Low cost linear regulator driver:

Groove V2
$10.99
Analog modulatable laser diode driver:

FlexMod P3
$35.99