You need a power supply. This is an Argon Ion laser, it's not nearly as simple as hooking up a diode to an LM317 and calling it a day. Operating voltage is ~90-110V
DC at ~8A (Up to 10A, only rated for 8A though).
You also need a lot of air going through the head (So you need a good fan, not just some computer fan you scavenged) ... these will dump about
1,000W of heat at full power, for a measly 0.015W of light output. Think: Space heater with a little pretty blue light and a big loud fan.
It may or may not work, you won't know until you find a compatible power supply to test. Could be an old tube, could have been sitting too long.
They are rated at 15mW 488nm - could do a little more in good condition.
I'd do some reading about Argon lasers (and gas lasers in general) on Sam's Laser FAQ before pursuing this.
Those lasers are fantastic! ~~~~ ( sorry was feeling upity ) you forgot to send a link for the laser.?
Define fantastic ... maybe if it was known working and had a power supply. But fantastic is subjective, some people don't want a 30lb space heater that puts out less light than a $5 eBay pointer. Getting an unknown condition tube with no PSU can be frustrating and take a lot of time and effort to get anywhere.
This is coming from someone that has owned several of these (and others, see signature for example) - and I
like them. But they aren't for everyone.