Hello Sankar,
I am impressed with all the efforts you are putting into modification of your car. I am just getting back to your alloys; take my word, don't go for used ones. I cannot give you all the reasons; so, only thing I would recommend that you put everything new as far as possible. I would never suggest a used part however chaep the deal is. As far as upgrade to 15", I would still suggest keeping 14" as long as you can. If you are tight on budget, wait for sometime, as selling your 1 k kms tyres for 5 k is loss. They can hold strong until you can manage to shell out the money for brand new.
BTW, the lights in your photos looked powerful.
You take care; a lot of things have inspired me. The first thing I will contact you in future will be with my audio system.
Regards, Manjax