The general thrust of it is not wrong, there are details that you could be doing different, and there are other ways to engage scarcities (that you probably know of).
General thrust: pushing forward a scarcity in an understandable way is great. It's easy to forget to that as MC, and then you end up with the "huh, my PCs are killing everything and it's working great for them" problem. So thumbs up.
Details: x-Barter is an abstract mechanicy thing, and as an MC you try to hide such facts. Misdirect, never speak its name, etcetera.
Barter in fiction isn't a number like today's cash mostly is - items of barter are things that people trade because they're useful. So, if people aren't working and the Hardholder isn't gaining rent, it's not just money he's missing out on, but stuff that could be crucial for the wellbeing of his hold. A sack of potatoes and a busted radio can be 1-barter both, but what they're needed for are different purposes, and so getting more barter-radios when your hold needs barter-potatoes can still be a problem.
Other ways (that you probably know of): You could not do barter calculus, have the hardholder be generous without much in mechanical hindrances, and instead just create a threat or front that's all about milking the hardholder's generosity for all it's worth, and then push that.
You could also not change a single thing in what you're doing currently and it'd still work great.