Well, if you can get ahold of said lasers, that's all well and good... the probable price has been commmented on. Just, be aware that they really are dedicated missile defense jobbies; 100 kilowatts isn't really enough to kill hard targets (IE, ones without explosive onboard) and they're going to be setup for much shorter ranges than we can see in, y'know, space. If you get something to hold still for a while (or at least not manuver much) so you can burn through a single spot, that's one thing, but don't be expecting quick or easy kills.
... though really, that's the closest a current hardtech weapon gets to being a practical ship-ship ranged weapon; the mechanics of trying to hit something that can do 10% lightspeed with a projectile that's moving (assuming equivalent topspeeds from the firer and firee) only about 3km/sec faster than that are kinda tricky.
Railguns are actually a *lot* more efficient at turning electricity into kinetic energy than coilguns; rail erosion's an issue obviously, but oh well. The Navy jobbies mentioned in that article are going to be pretty close to state of the art for something that's intended to eventually live outside a laboratory. Note from interpreting the article, that a plain vanilla 5" gun ends up at about 8MJ of kinetic energy, though obviously lower muzzle velocities.
If you want a fairly cheap, practical hardtech gun capable of very high muzzle velocities, google the SHARP light gas gun. Basicially works like an overgrown air rifle, but with hydrogen instead of air (preferably very hot hydrogen at very high pressures) Because the speed of sound in hydrogen is a lot higher than in air (or burning cordite) the maximum muzzle velocity's higher as well. Been in use for decades; NASA has a bunch they use for micrometeorite simulation.
There's also ram accelerator cannons that are capable of even higher velocities, but I'm not entirely sure they've been experimentally demonstrated to work.
... though really, that's the closest a current hardtech weapon gets to being a practical ship-ship ranged weapon; the mechanics of trying to hit something that can do 10% lightspeed with a projectile that's moving (assuming equivalent topspeeds from the firer and firee) only about 3km/sec faster than that are kinda tricky.
Railguns are actually a *lot* more efficient at turning electricity into kinetic energy than coilguns; rail erosion's an issue obviously, but oh well. The Navy jobbies mentioned in that article are going to be pretty close to state of the art for something that's intended to eventually live outside a laboratory. Note from interpreting the article, that a plain vanilla 5" gun ends up at about 8MJ of kinetic energy, though obviously lower muzzle velocities.
If you want a fairly cheap, practical hardtech gun capable of very high muzzle velocities, google the SHARP light gas gun. Basicially works like an overgrown air rifle, but with hydrogen instead of air (preferably very hot hydrogen at very high pressures) Because the speed of sound in hydrogen is a lot higher than in air (or burning cordite) the maximum muzzle velocity's higher as well. Been in use for decades; NASA has a bunch they use for micrometeorite simulation.
There's also ram accelerator cannons that are capable of even higher velocities, but I'm not entirely sure they've been experimentally demonstrated to work.