The looks and performance of both the variants are the same. The only difference one will see is in prices and features, Sportz variant has a navigation system, adjustable steering, rear camera, fog lights, etc. You can click on the following to check the complete comparison of both the variants - Comparision.
For the availability and prices of the spare parts, we'd suggest you connect with the nearest authorized service centre. Click on the link and select your desired city for [service centers@https://www.cardekho.com/Hyundai/car-service-center.htm
For this, we would suggest you to connect with the nearest service center as they would be the better people who can assist you with the possibilities. You can click on the following link to see the details of the nearest service centre and selecting your city accordingly - Service centre.