As much as I'm also a little on edge about getting my Tavor, I don't suspect anything fishy relating to their website being down. I've checked, and the domain name isn't expired, the DNS settings seem to be valid, the server can be pinged and the traceroute are good, but their server won't respond on ports 80, 443, 22, or 21. I can't say with certainty, but these symptoms can often be caused by:
A) A machine that has spiraled out of control(overloaded either naturally or by a DOS attack). In these situations, the machine becomes too busy to respond on the usual ports, but can resume operation when the excess workload is reduced or removed. This also extends to problems with a virtual private server choking while the host system tries to cope with other VPS's sharing the hardware.
B) The server has an internal hardware problem, such as a dead drive, bad ram, cooked motherboard, etc. In some situations like this, the machine can continue to run some services, but others will fail as soon as they try to access the damaged components.
C) Someone or something has accidentally turned off/disabled the internal daemons(software) that listens on the ports for connections.
D) A security update or patch goes wrong, and activates firewall rules that shouldn't be running or has some other negative outcome.
etc., etc., etc
Anyway, at this point I'd say there is no need to panic. I'm sure CanadaAmmo is trying their best to get the website up and running again. I wouldn't be surprised if it takes a little while to resolve as they are hosting with "DreamHost", a large, cost effective and reputable company, but with a huge client base which makes it tougher to give customized, drop everything service to any given client when things go wrong(especially if many clients are affected by the same outage/problem).
So, hang tight, I'm sure all will be well...
(ps. Remember, I'm in the exact same boat as you are: I pre-paid for my Tavor long ago. I'm not happy about the delays, but at this point I don't believe anything sinister is afoot...)