any other dac/amp that are portable, where I can use it with my ipod touch and 1964 T.??
The Pico Slim is only an Amp. Not a DAC/Amp. But there is a bigger Pico DAC/Amp, just not the Slim.
For the iPod Touch your portable DAC/Amp options are the Fostex HP-P1, or Go-DAP (but with a dock extension cable like this). There's also the CLAS but it's DAC only & you'll need another portable Amp (like the Pico Slim, RX2, etc.).
The other USB based DAC/Amps (RSA Predator, iBasso D-Zero, E7, etc.) can't really be used directly with the iPod Touch. Those USB DAC/Amps are more for computer desktop/laptops.
Hmm...if your budget is $200 & you want to use it with your iPod Touch, then I'm thinking that you may have to use an external Amp only (& use the internal iPod Touch DAC).
You still could buy a portable DAC/Amp but use the Amp portion only with the iPod Touch. That's still not so bad cos you still could use the same DAC/Amp with your desktop/laptop if you want full DAC/Amp functionality.