Are Siemens hearing aids still available for purchase and is product support available?

In short, yes. If you purchased hearing aids a few years ago your hearing aids were a "Siemens" instrument. Signia is the name that has been taken on since Siemens branched out their hearing aids as their own entity. You can still purchase this manufacturer with most audiologists. Just know the name of their hearing aids are now Signia. Same instruments, different manufacturer name. Product support for these instruments can be done at any audiology office (call first to ensure they have the software needed to fine-tune your hearing aids) given they provide services to Siemens/Signia hearing aids.  

A few years ago Siemens made the decision to separate their hearing aid business as a stand-alone company.  At that point they began to rebrand using the new name "Signia".  They are still the same company with the same products including service and support for all the older products.  What they have done differently is increase their research and development which has produced a number of significant changes and upgrades in their product line.  It is now arguably one of the best hearing aids available anywhere.  The newest model called the NX incorporates own voice processing to improve the way a patient's own voice sounds while wearing the hearing aids.

Siemens hearing aids are available.  You will now see the company has re-branded and is now called Signia.  All Siemens devices are supported through the Signia brand.

Yes, Siemens aids are available. They are co-branded under the Signia name. In fact, the products now have Siemens logo on one side and Signia on the other. 

Yes, Siemens hearing aids are still available for purchase and support! They are now under the brand name Signia.