I used to buy mine from my dealer. You will need to go to the RA website to find out about threads in bulk.
I also sell embroidery threads-Outback Threads. I am now using them exclusively and find they are very good.They stitch out nice and smooth.
They are also much cheaper.
Click on the link and check them out.

I do not use RA threads. I get my threads from www.scrapdragon.com.au
This site is owned by my daughter so I get the threads is lieu of babysitting. LOL. I am in a win win situation. Marg

I buy online from Shoppers Rule, even with the cost of shipping it is still cheaper than I can buy it here, if I could even buy the colours I want, here.

Join their members club (free) and you receive bonus discounts as well as earning points for discounts.

The Enviro thread tubes are absolutely brilliant for storing your threads. keeping them protected from dust, heat and light, you can hang them from hooks on a wall.

I recommend shoppers rule as my favourite online shop for everything sewing, except material.
hope this helps, Meganne

Why don't you check out Redrockthreads.com? They are in the states but don't overcharge for postage. If you contact them through their site you might be able to get a discount since you're wanting to buy in bulk. I know normally poly sells for $4.75-1100,
$10.95-5500yds. & rayon is $5.50-1100, $12.95-5500.
Do contact them as nothing ventured is nothing gained. BTW, these are great people to work with.

Thank you, everyone. Now I have an even harder choice, with all the great options.