How can I write this letter better? I require the modification of the 'body' of the letter only.That's why I have not written the other fomalities like "yours faithfully" and address, and stuff like that.

Dear Sir,
First of all, I wish to congratulate you on your plans to organize an exhibition exclusively on orissan patta paintings at Delhi. Personally, I believe that this certainly would be a wise step as it will not only facilitate popularity of paintings of this kind but it also will be a source of inspiration for the painters.

Prior to any concrete move as to contributing paintings to the exhibition, we need to have an idea about the time when such an exhibition is supposed to be held. We will also need to know about the size of the paintings required for the exhibition.

Our art studio called “Jagannath arts” is only one year old and we have participated twice in the exhibition only at Mayapur. Keeping in mind our limited funds, we consider it important to let you know that we are prepared to meet the expenses relating to the making of the paintings but we are sorry to say that we won’t be able to cover the freight, insurance, and other incidental expenses.

Some quick comments for you.

Para one fine apart from - facilitate popularity of paintings of this kind - increase the popularity of paintings of this kind.

Para 2 - Before we can make any concrete agreement to contribute to the exhibition, we will need to know when it will be held and what size paintings you will accept.

Para 3 - Our art studio, 'Jagannath Arts', is only one year old and we have only participated in two exhibition previously. Final sentence ok.
Thank you sir