www.lautsprechershop.de has many DIY Kits that feature some of the top names in premium audiophile quality drivers, such as, Scan-Speak, Seas, Excell, Vifa, Peerless, etc. Many of them were designed by a top European audio magazine. What is especially nice is the descriptions of each speaker so you have a good idea of what to expect from the speaker once assembled. They come with top quality parts and most have an option to upgrade the crossover parts to top-of-the-line premium parts for only a few dollars more. The Lautsprechershop does ship to the USA. If you are wondering about currency exchange it will converted for you automatically by PayPal to the current day's US Dollar exchange rate once you enter your choice of kit into your shopping cart.
You can also buy individual parts and DIY speaker supplies, although I would buy those things from domestic suppliers, such as,
www.madisound.com and
www.parts-express.com, etc. to avoid the shipping costs.
If you have any questions, email them.