We have recently specced a SWAN analyser-which is a swiss manufacturer- comes ready assembled, very easy to install. online approx. $5K is the ballpark figure, and this is one of the cheaper brands.
Very widely used in EU- but an excellent unit, I also asked for reference sites and contacts(operators/instrument techs- not managers), who all gave a very positive feedback.
Sorry but $1K is an unrealistic figure for a online Chlorine instrument.
It also has one of the simplest Profibus configurations I have seen for a while.
Other manufacturers inc, HACH, Siemens (formally Wallace & Tiernan), E&H, Prominent, ABB, Capital Controls. Sorry but a lot of the big players in this are european.
The acid in the solution may be a problem for most instruments. Although it will depend on what exactly the pH is and wether it is consistant. You may require pH correction probe for the analyser to give accurate feedback.
Please let us know how you get on.
Regards
Stablefordd.
Calgary