The binders on that website are made for daily wear. Just a few hours in it would be fine. It may take some getting used to if you've never bound before, so that would actually be perfect for you. For sizing take some measuring tape and:
(fullest part of bust + under-bust measurement) / 2 = your size
A good indicator of when you should definitely take your binder off is if you start feeling sore or have any trouble breathing.
Ebay and amazon are great for cheap glasses.
Two-toned black/purple wayfarers:
http://www.ebay.com/itm/Black-Purple-Med...2a320050a4
Bright purple wayfarers:
http://www.ebay.com/itm/NWT-CLEAR-LENS-W...3f12123f93
Narrower style with a kinda cool gradient:
http://www.ebay.co.uk/itm/3-PAIRS-NEW-RE...5af299dac9
Not purple, but I think a Cecil costume might look good with horn-rimmed glasses:
http://www.ebay.com/itm/Eyeglass-Frame-C...3654815%26
I didn't look into the reliability of the sellers themselves for those links, but with ebay - lots of positive reviews are a good sign. Just check the comment sections to make certain they were posted by real people and it's not the seller mass-posting reviews from dummy accounts to make their store look better. It's generally pretty easy to tell. I didn't check amazon myself and these are just some quick finds. I only searched things like "purple wayfarer" or "purple glasses" and narrowed the price range to 10$ or less.
(fullest part of bust + under-bust measurement) / 2 = your size
A good indicator of when you should definitely take your binder off is if you start feeling sore or have any trouble breathing.
Ebay and amazon are great for cheap glasses.
Two-toned black/purple wayfarers:
http://www.ebay.com/itm/Black-Purple-Med...2a320050a4
Bright purple wayfarers:
http://www.ebay.com/itm/NWT-CLEAR-LENS-W...3f12123f93
Narrower style with a kinda cool gradient:
http://www.ebay.co.uk/itm/3-PAIRS-NEW-RE...5af299dac9
Not purple, but I think a Cecil costume might look good with horn-rimmed glasses:
http://www.ebay.com/itm/Eyeglass-Frame-C...3654815%26
I didn't look into the reliability of the sellers themselves for those links, but with ebay - lots of positive reviews are a good sign. Just check the comment sections to make certain they were posted by real people and it's not the seller mass-posting reviews from dummy accounts to make their store look better. It's generally pretty easy to tell. I didn't check amazon myself and these are just some quick finds. I only searched things like "purple wayfarer" or "purple glasses" and narrowed the price range to 10$ or less.