dear bhai
glaze just to temporary hide minor imperfections and give boost to paint, glaze dont have longer life so after its application u have to seal the finish with any sealant or wax
while polish permanently remove the minor imperfections and give boost to paint after than u can seal the the finish with sealant or wax
now its upto u , u want to hide or remove minor imperfections 
not sure about price , roughly between 2k to 2.2k each
yes both avilable in pakistan
for meguiars u can go to optimum motor sports and for mothers autoline 