Acelere are neither cheaper nor costly. If you want more comfortable ride can go for brands like Michelin,Yokohama, Bridgestone. But they did not last long more than 30000 kms. If you want long lasting tyres and ready to compromise on comfort level then can consider JK, CEAT, MRF Apollo Amazer XL etc.
My stock Apollo Amazer xl lasted for 39000 kms
I will suggest you to replace all four tyres with brand new tyres. Old tyres can be sold to tyre dealers.