If you want a physical copy of Timecop, you might have to actually travel back in time to acquire it, because finding one in 2014 is more challenging than I expected. For whatever reason, the demand for Timecop isn't sufficient enough to provoke retailers into keeping a ready stock of Timecop DVDs, videocassettes, or Blu-rays. It isn't on Netflix streaming at the time of this writing, and, in fact, Netflix's supply of Van Damme movies is woefully anemic (it is only seven titles deep, one of which is the sixth Universal Soldier installment, which is the Van Damme equivalent of the fifth Police Academy). You can order a copy from Amazon, but if you're in a situation where you need to watch Timecop immediately, which I suspect you are, then you need to rent or buy it from Amazon's streaming service. Or, you can light some incense and meditate in front of a Timecop poster and wait for the film to beam itself into your consciousness (you will need to have already purchased a Timecop poster for this particular strategy to work).
The only other option is to glide through a wormhole back to September of 1994 and buy a ticket to see Timecop. This might actually be the best option, because that way your anniversary celebration will be mistaken as excitement for the release of Van Damme's thrilling new blockbuster, as opposed to an unhealthy compulsion to chronicle the oddest corners of pop culture history.