Entry level WDM gear?

[Jeff Kell <jeff-kell () utc edu>]

Apologies if this is a "dumb newbie" question, but this is one area of
networking where I remain a virgin :)

We have a local loop fiber to a regional fiber hut that has served us
well for several years.  It's carrying a 1550nm ER 10G circuit at the
moment, but we're looking at another one, possibly two (or more) in the
near future.  Getting another dark pair is "complicated" so we're
exploring options to [C|D]WDM multiple lambdas over the existing fiber.

Ciena/Cyan/etc are way over our non-existant budget...  what is the
going recommendation to throw say 4-8 lambdas over a dark pair without
breaking the bank?  :)

Jeff