Rear suspension HELP needed! (PICS)

Hey guys. My name is Tom and I have a 2013 Tacoma double cab long bed.

I run a contractor cap for work and regularly have tools and etc in and on top of it.

I have been running it on there for a year and have had some concerns with the weight of the cap and tools wearing on the stock rear suspension. The truck sits pretty much dead level.

My question is, is the stock suspension sufficient to withstand the weight that is constantly on it? Am I at risk of something breaking and causing a serious accident? If not, what is my best option to counteract this?

I have looked into new leafs (Dakars) and was told I then would need longer shocks, u bolts, etc. So I then looked into the whole lift kit and with shipping and coil assembly I am looking at 1500$. I was not looking to spend that much as I do not off road and cannot justify a lift. (Although I love the way it looks and if money was no option this is what i would so)

 

Check these out man! Could be a good option
https://www.tacomaworld.com/threads/installed-firestone-ride-rite-air-bags.273337/

https://www.tacomaworld.com/threads/firestone-airbags-for-tacoma-any-good.185357/

 

Install airbags if your worried about the weight

Edit: what redtacoma said