HSI has long specialized inthe "rescue" of data from legacy systems; we have been able to recover data from undocumented custom programs without source code. While it isn't possible to promise success in such cases, we have not missed yet. We have tools for and experience in working with many different types of older systems and file orgainizations, and a background in crytography doesn't hurt.
If your system is based on the THEOS operating system, please see our page on our services associated with that system.