It was most likely manufactured by Hedstrom. The sharp main frame tube bend is a distinguishing design feature of later Hedstrom trikes. I also notice the seat post hole is square and Hedstrom did use square seat posts on many of their tricycles. Not sure exactly what year. If you do a Google image search you'll see some Hedstrom tricycle photos showing models nearly identical to this one. Hope that helps a little in your search for information.
Unless you are truly dead set on restoring this particular tricycle for sentimental reasons, you would be money ahead to simply purchase a vintage tricycle in great condition off ebay or craigslist. In all honesty even restored your tricycle has very little to no collectable value. Not trying to discourage you from restoring it if you want but just pointing out the fact that it will probably be worth less than the time and money you put into it.