a standard letter has far less effect than a letter which is individual. Also, you should always ask your question, or at least intimate it, at the beginning of the letter. If they are being swamped, they will not get to the end of you letter, but will only read it to get the gist of your message. Be effective. Write clearly and concisely. And make it short. Anything more than a page, leaving a generous space for address, signature block and date, will not get the attention you seek.