Convert DAT & IDX Files into MS SQL Server

This is for an old customer using old windows-based SCADA system (should be around 1996) and have these file extensions. This system stored database in these DAT and IDX old file extensions. The software vendor is no longer around and we would like to do some data extraction. We do not know what software to use to read the data files. We do not know what database they are using. The old system has a function to store all their data into these DAT and IDX file extensions as database for up to 3 months only. They want us to extract the data files and convert into MS SQL Server database otherwise the files will be deleted after 3 months auto purging. Phase 1 is to convert DAT and IDX data files into MS SQL Server database. I will provide you a sample DAT and IDX data files to try. Phase 2 is to sync DAT and IDX data live with MS SQL Server. Every insert, delete and update on the DAT and IDX data files will be immediately sync to MS SQL Server. Please bit for phase 1 first for this case. Thank you.