You could say something like this:

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Hi!

My name is Rebecca LastName. I will be opening an online boutique on Date. You can take a look at my website here: http://yourwebsiteurl.com. I am interested in carrying your product line. I think your line will really speak to my customer base which is blah blah blah (make sure you check their website to see their target market).

You stated on your website that you offer your items wholesale. Would it be possible for me to see your wholesale pricing?

Please do let me know what information you need from me. If you would like to speak by phone, you are welcome to call me at 800-555-1212.

Thank you for your time.

Rebecca
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I would keep the e-mail as short as possible. There is no reason to drone on and on - people just don't have the time to read those e-mails :)

Good luck!

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