No one can really give you advice about this without knowing what's in your tap water. At a minimum, you need hardness and alkalinity numbers in order to make any scaling estimate, and to choose a treatment that might avoid scale buildup problems.
Having said that, if you are on the Abilene water described here: https://saveabilenewater.com/wp-content ... _web-1.pdf
, you will have scale buildup problems if you don't soften that water. A fridge carbon filter won't do the job, and any system that will is going run you more than 100 bucks.
That Abilene water is especially problematic because of the 87 - 166 ppm chloride levels. This will not cause scale problems, but may cause corrosion problems. Best advice here would be to go with a reverse osmosis filtration system to remove that chloride. (Carbon filters effectively remove chlorine, chlorite, chloramine in the small levels added to disinfect the water supply, but will not filter out that chloride.)
I think your most practical option would be to repair your Flojet system and use carboys of spiked purified water under the sink. The R Pavlis water is simply distilled or RO water with 50 - 100 mg/L of potassium bicarbonate. On a 5 gallon carboy that would be about 1 - 2 gram of potassium bicarb per 5 gallon fillup. It will have a nice non-corrosive alkalinity, will deposit no scale, and most folks say that it produces fine tasting espresso.
P.S.Summarizing the numbers in that 2017 City of Abilene report that I linked above:
Total hardness 182 - 346 ppm
Total alkalinity 111 - 127 ppm ("temporary hardness" would be roughly equal to this)
Calcium hardness 138 - 208 ppm (calculated from Ca ion)
Chlorite ion 0.9 ppm
Chloride ion 87 - 166 ppm
Sulfate ion 63 - 212 ppm
TDS 366 - 717 ppm
Conductivity 698 - 1340 umhos/cm (would read 349 - 670 ppm on typical inexpensive TDS meters)