300 Jumbo Bricks

General Information
The following information has been collected from original newspapers, catalogs, and magazines, some of which are freely available for reference below. The rest can be found in the site’s gallery. No aggregate catalogs (BrickLink, Brickset, etc.) were used.
Advertised Part Count(s): 30 pieces
First Year Confirmed Available: 1972 (USA)
USA Only.
Most Likely Retirement Date: 1972
Samsonite's toy division closed in late 1972.
Last Year Seen Available: 1973
The Duluth News Tribune, September 30th, 1973
Aliases: Lego Jumbo Bricks, Lego Preschool Set, Samsonite Lego Jumbo Bricks
Retail Price(s): $3.99 - $5.95 (USA)
Discounted Example(s): $2.99(1972), $2.49(1973)
Rarity Score (Rarity Index): 6/7
Known Box/Packing Variants
There are no known variants and it is likely none exist.
Box/Overview
The 300 Jumbo Bricks Set is the most innocuous set of Samsonite's 1972 toy line redesign—that is, it exists and there's not much to talk about for now. It is a redesign of the 1969-71 044 Jumbo Brick Set, though with a slightly different assortment which we will cover below.
About the most interesting thing about it is its shocking rarity relative to other 1972 sets. It's an extremely hard set to find any images of, and I've personally not seen an example come up for sale.
As a result, we are left to the internet to see images of the box. This one comes from BrickLink:

And the top flap, which is often missing on all Samsonite cube-style boxes:

Adverts are sometimes useful in providing more angles:

This one gives a better view of the side, which is just reusing the same image:

Contents
For whatever reason, the 1972 Dealer Catalog shows an image with green Jumbo Bricks, but the set likely never contained those. Instead, see the image featured on the final box in which it had yellow, blue, and red (same colors as on the box):

However, to complicate things further, FAO Schwarz shows the set containing red, white, and blue bricks, as did its predecessor:

I do want to caution the above example, as it very well could be a reused image from prior years.
So for now, without images from a surviving example, I have no idea what the actual retail assortment was. If I had to guess, given the relative commonness of yellow Samsonite Jumbo Bricks, the 300 could very well have contained them. Otherwise, the only distribution channel for them was the very limited DP60 Jumbo Bricks Set from Discovery Playthings, which seems unlikely. I could see it going both ways considering nuance from Why did US Samsonite lose the LEGO license?
BrickLink gives an inventory with red, white, and blue and vaguely cite a description instead of a surviving example. By description, I have no means to confirm it and it could very well have been a misapplied description. As we saw with other Jumbo Bricks sets, the year they released they often inherited materials/descriptions from their predecessor, even if they were made inaccurate by the new assortment.