A composition match, not medical advice.
D Retcal 500mg/500IU Tablet 10s contains Elemental Calcium (Calcium Citrate) 500mg + Vitamin D3 (Cholecalciferol) 500IU, as a tablet. It is made by Retra Life Science Pvt. Ltd.
No, it is sold over the counter. Ask a doctor or pharmacist if you are unsure whether it suits you.
Yes. Calcium 500mg and Vitamin D3 500IU Tablets IP is a Jan Aushadhi medicine with the same salt, the same strength and the same form. On JanAushadhiOnline it costs ₹8.25 for 10 tablets (₹0.8 / tablet), against ₹6.5 / tablet for D Retcal 500mg/500IU Tablet 10s at its printed MRP — 87% less per tablet. Ask your doctor before changing a brand.