I haven't seen the data yet and there's likely a better way of doing this, but worst case - couldn't you just script replacing :00: with -00- (through :59:)? Then, if you wanted, replace ':' with a better delimiter and then replace the -00- back to :00:?

I'm assuming there's a better way w/ regex but I'm not great with regex. Could probably find that with a few minutes of google though, just replacing the pattern of :##: with -##- using numeric wildcards.