Wondering why you want to filter the 6 M band so sharply? Is there some horrendous adjacent channel interference you need to knock down?
Anyway, the LC filter is impractical. Once you add in and simulate the real-world components with their finite Q and series resistance and so forth, you will not be anywhere near the desired response, and have a ton of loss to boot
That is after all why folks go to the trouble, size, and expense of cavities and the like. If small LC were possible, everyone would already do it.
Re xtal filters - you may be able to do this, although loss is gong to be pretty high. And it would be pure luck if you were able to get xtals on the frequency that you wanted.
You -may- be able to build a reasonably low loss filter of a MHz or there-abouts with a tweeky LC filter using good quality components, beefy inductors, etc.... Most often, one would want to filter the width of the 6 Meter band in order to eliminate out-of-band overloading signals - this would be a good practical design that you may be interested in trying
This difficulty in get sharp narrow-band filters up in the MHz and 10's, 100's and higher of MHz range is exactly the reason that hetrodyne receivers were developed. And also why super high-dynamic range SDR was developed. It's easier to filter at the low IF frequency in the case of a hetrodyne RX, and narrow band filtering is done digitally at baseband in the SDR software program.