Respected Sir/ Madam,
I am __________ (name) and I am writing this email to state that our company is going to organize an event on that day on the occasion of __________ (mention occasion) and on behalf of __________ (company name) I would like to book your restaurant for __/__/____ (date) for _________ (lunch/ dinner/other) of employees of our company.
Courteously, the gathering would be of _________ (mention number of people) and the timings for the same would be __:__ (time) to __:__ (time). This is to request you to kindly acknowledge the availability and send the quotation stating the booking amount along with other charges.
You may respond to this email or call at __________ (mention contact details).
__________ (Your name),
__________ (Contact details)