Periscope guards for a Sherman

Couple of non-PE solutions, one is a white metal set by Schumo-Kits from Germany that run about $6 for a set of 5:
 http://www.axels-modellbau-shop.de/katalog/en/135-Military/Accessories-135-scale/Periscope-Covers-for-US-Tanks-Sherman-Pershing-Stuart-etc::7133.html  

Second option is Shapeways 3D printed ones that are $13 for a set of 50 guards.
 http://www.shapeways.com/model/879545/c100914-guard-assembly-periscope.html 

Thanks guys.  I'm surprised none of the big name companies have come out with a detail set.  I know Eduard, Verlinden and others have their PE sets.  But I also know there are some models with plastic guards in them already.

So, two more questions:

1.) Is it incorrect to show the sherman without the guards?

2.) Are there any tutorials on making your own guards?

-Jesse

1)  it depends on the time frame -- mid-war, they started to be added to the Shermans.

Go for the Shapeways option.  I have 'em and haven't looked back -- the time saved in making them myself more than is worth the few dollars.

I would agree with Roy; 50 for $13 seems like a deal and more than enough for all the Shermans I have. I don't have them myself, but they are on my want list when I get to some kits.

For me, it's the economics of time and motivation.  I've got too many shelf queens staring at me in my workroom.  Almost all my projects involve super-detailing and often, heavy conversion and/or scratchbuilding.  I've had to realize that unless I get in a long groove with one project (getting it ready for painting), that it may be de-railed by loss of motivation, a research gap, waiting for some pictures/documents, etc.  Thus, I try not to spend extra time on sub-assemblies that can be completed by the expenditure of a few dollars -- such as the addition of accurate, pre-made periscope guards to my Allied tank projects.  Plus, they're much more symmetrical than I can scratchbuild myself -- win-win scenario!

I need to use that energy on other trickier assembly projects!

So in my initial post, I had ask about a kit that has an extra set of periscope guards.  Well, I found a kit that does have an extra set (4 guards).  It's the Academy M4a3 Sherman 105mm Howitzer & M1 Dozer Blade.  The funny thing is, I have it under my work bench.  I didn't even think to look in the kit when I made my initial post.  By the way, it's parts F4 and F5.