If you found both control arms for $50 @ with the bushings, that's a good deal. As far as conpared to the OEM, since you didn't list specs, it's impossible to know. But as a (retired) ASE Tech, I can say most 3rd part parts meet or exceed OEM. You have to remember that Honda doesn't make rubber parts, they buy them from a 3rd party too
As far as replacing them, it's been awhile since I had my 04 on stands, and don't remember. You don't need any special tools, but if you do it at home be prepared to curse as you try to loosen 10+ year old bolts and nuts. Also remember that the LCA is mounted to the strut/spring, so you need a way to deal with the spring wanting to fight you.
As far as them being safe or not, without seeing them, I can't say. Are they 'worn' or 'worn out'?. I wouldn't be surprised, or care about a little bit of small cracking, what I'd look for were large cracking in the rubber or separation. At that point the car will want to wander on the road as the wheels will not have a solid point on the car to maintain alignment.