The short answer is to have the home inspector check. They may not do this normally, but I am sure they will if you specifically ask them to. If not, then an electrician would be able to check for you.
You probably could have figured this out yourself, but there really is no other way other than calling the factory, assuming they are still in business, not bought by another company, and someone there actually knows.
So, honestly, getting a professional in there to check is the only real way of knowing. This is very important as aluminum wiring is dangerous under certain contitions.