I haven’t used open cart for a while and when I did it was the joomla embeded version (virtually identical but not standalone).
You should be able to script virtually anything with a bit of work but not looked into the API modules - it obviously depends on what calls/features the modules offer. there were a few API modules available.
If you want a bit of background in to scripting an intergration take a look at my PMS intergration or kendash/q’s timetrex setup.
I might sugest my PMS topic might be better if your less familier with scripting etc as I started it as a tech savey jscript novice so starts faily basic.
The PMS topic is hear;
If I didnt have so much on I might have been a bit more proactive as is something I have wanted to look into to have a webshop integration to offer to clients. However if you do go ahead and get stuck I will hapily help where I can if you tag me @JTRTech.
Try and share your working in this or a fresh topic as it will help anyone supporting you to see your setup and potentially help others looking to do similar, plus i would be intriged to see how you get on.