Is the ECO (External Crystal Oscillator) available with all devices in the PSoC 1 faily?
There is an application note available on Cypress website which talks in detail about the points one should take care while using ECO. You can access this appnote at the following link - http://www.cypress.com/?rID=2844 (AN2027 - PSoC 1 - 32.768 kHz External Crystal Oscillator)
This is start of thread for Cypress about a selector tool needed -
To see which device supports ECO, refer to "Choosing a PSoC 1 Device" section of application note AN75320 - Getting Started with PSoC 1 - http://www.cypress.com/?rID=58639
Short answer is no, not all parts in PSOC 1 have ECO.