Leaf Blowers

I have a 125BT model TJ027D-A55..with the TK TZ-11 Carb...Your Authorized dealer stated needed to replace carb...$175.00...I can by a new blower for this???(and it would be another brand) Went to rebuild myself...I replaced all components accept 2....and in researching the fuel flow issue...pretty sure this is the problem...cant give you part #'s...cause they are not listed in parts manual. Under the diaghram at the needle valve...there are 2 brass components stacked together...one looking like a backflow preventer...which does not appear to be letting fuel through either way...why are these 2 parts not listed and how can I get them? Any true mechanical component should be completely rebuildable...no reason to just replace....just replacing is normally due to just poor mechanics...Please advise where these components can be purchased.
Thanks