Treasury technology vendor Wall Street Systems said today that its deal to acquire the assets of Thomson Reuters Corporate Treasury Manager will close at month’s end and that it plans to integrate the Treasura workstation with two other treasury products.

Treasura has about 300 users, says Larry Ng, managing director of corporate development at Wall Street Systems (WSS).

“The Treasura business is software-as-a-service focused on cash management in North America,” Ng says. “We actually have full treasury functionality, so there’s a potential upsell option for us, to sell a full treasury solution to their cash management clients.” He says WSS will also sell Treasura’s more extensive U.S. cash management capabilities to its existing treasury clients.

And within the next year or two, Ng says, Wall Street Systems will integrate Treasura with two other products: City Financials, a treasury management system that it purchased last year, which he describes as having Eurocentric cash management capabilities, and Wall Street Treasury.

“With this latest acquisition, we have enough of the underlying assets to integrate into a great mid-tier offering,” he says.

Wall Street Systems is buying the assets that Thomson acquired in 2004 when it purchased Vancouver-based Selkirk Financial. Ng says most users of another Selkirk product, Treasury Manager, have migrated to Treasura.

Craig Jeffery of Atlanta-based consultancy Strategic Treasurer revealed that a deal was in the wind on his blog on Thursday.

On Friday, Jeffery described the deal as good news for companies that use Treasura, noting that Wall Street Systems is a big player in treasury technology. “It’s probably a better thing for Treasura users that they’re in a place that cares about treasury workstations,” he says.

This is Wall Street Systems’ third big transaction in less than a year; in 2010, in addition to buying City Financials, it acquired Speranza, a provider of electronic bank account management software.

Ng suggests the company’s buying spree is complete. “We finally feel we have enough of the underlying assets to be very strong in the mid-tier treasury market,” he says.

Asked to estimate Wall Street Systems’ market share in the wake of its acquisition of Treasura, Ng says, “in terms of dedicated treasury solutions providers, it’s really us and SunGard, and we’re probably equal in size in the treasury space.”

Terms of the deal were not disclosed.

For more on Wall Street Systems, see Wall Street Systems Buys City Financials and Wall Street Systems Buys Speranza.